How to Stop Tree Roots From Plugging Sewer Lines

Keep invasive tree roots from plugging your sewer line by boring them out with an rented auger, cutting the trees or calling in pros. The pros will bore the line open for you, treat the roots with poison, replace the old pipe or reline the old pipe.

What to do if tree roots clog your sewer pipe

Photo 1: Camera in the pipe

A pro can run a camera down the sewer line to determine exactly what's clogging the pipe.

If you live a wooded lot and have problems with tree roots invading your sewer system and clogging it up, don't assume you have to cut the trees down! As you can see from the photo, the tree roots work their
way through cracks or joints in older sewer lines made of
clay tile, cast iron or an asphalt composite style called
“orangeberg” piping. The roots are seeking that nutrient rich
soup you're sending down the drains and toilets
(there's no accounting for taste). Clay and cast iron are
rarely used anymore because of those loose-fitting joints
that tree roots can penetrate. These materials are also
heavy, hard to work with, expensive, brittle and prone to
breakage. Nowadays nearly all sewer lines are made of
plastic pipe—it's cheap, tough and lightweight, and the
joints are impervious to tree roots.

You've got three options, none ideal: Continue reaming
the lines periodically, cut down the trees, or call in the pros.
Larger sewer-cleaning companies will ream out the line
or actually send a mini video camera inside the pipe to
determine exactly what the problem is. They'll find out
if the line is crushed, cracked, or sloped improperly, or if
tree roots are worming their way through cracks or loose
joints. Then they'll recommend a course of action, which
could be:

Digging up the old line and replacing it with plastic.

Treating the line with a poison formulated to kill
nearby tree roots. That way it'll take much longer
for new roots to cause problems. These poisons
are designed to kill just problem roots—not the
whole tree.

Sealing the line by lining the existing pipe with an
internal plastic fabric and cement. Companies have
been doing this for years on larger lines and are just
beginning to line residential ones. Chances of finding
a local company that does residential sewer lining are
slim, but it doesn't hurt to ask.

One of our editors has the same recurring problem
as you. He got tired of the $100 service call every year
(always on a Sunday while entertaining friends), so he
bought his own $400 power auger and cleans out the lines
himself. You can also rent one.

Roots in a Sewer Line

Roots commonly enter old clay tile sewer lines at open joints or where the tile has been cracked or crushed.